.box {
  display: flex;
  flex-direction: column;
  width: 100%;
  height: 100%;
}
.box header {
  height: 1.062802rem;
  background-color: white;
  text-align: center;
  line-height: 1.062802rem;
  font-size: 24px;
}
.box main {
  flex: 1;
  position: relative;
}
.box main p {
  width: 100%;
  height: 100%;
  background: url(../img/advertisement-bg.jpg) no-repeat center;
  background-size: 30.917874rem;
}
.box main h2 {
  font-size: 0.57971rem;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  color: transparent;
  white-space: nowrap;
  animation: holdOn 1s linear forwards;
}
.box main div {
  width: 2.415459rem;
  height: 0.966184rem;
  line-height: 0.966184rem;
  border-radius: 0.483092rem 0.483092rem 0.483092rem 0.483092rem;
  text-align: center;
  background-color: white;
  border: 1px solid #bbbbbb;
  position: absolute;
  top: 0.676329rem;
  right: 0.555556rem;
}
@keyframes holdOn {
  25% {
    color: rgba(255, 255, 255, 0.2);
    font-size: 0.772947rem;
    top: 60%;
  }
  50% {
    color: rgba(255, 255, 255, 0.4);
    top: 70%;
    font-size: 0.917874rem;
  }
  75% {
    color: rgba(255, 255, 255, 0.6);
    top: 80%;
    font-size: 1.014493rem;
  }
  100% {
    color: #ffffff;
    top: 75%;
    font-size: 1.15942rem;
  }
}
